ESO Spanish Users : ESO Telescopes P89

Table of Contents La Silla Paranal Chajnantor La Silla NTT Telescope: The New Technology Telescope is an Alt-Az, 3.5-m Ritchey-Chretien telescope hou

Table of Contents La Silla Paranal Chajnantor La Silla NTT Telescope: The New Technology Telescope is an Alt-Az, 3.5-m Ritchey-Chretien telescope housed in a rotating building designed for optimized air ow. Its thin meniscus Zerodurmirror is controlled in order to maintain the optical figure so that the total aberrations are smaller than 0.1500(80% encircled energy) -- the NTT was the first telescope to be equipped with “Active Optics". The instruments SofI and EFOSC2 are permanently mounted at the two Nasmyth foci. The telescope has a pointing accuracy of 200RMS; objects can be observed at zenithal distances from 2o to 75o. Currently, moving targets can be observed only with differential tracking (not guiding). Moving objects can be followed for up to 15 min with a tracking error smaller than 0.500. 3.6-m telescope:The 3.6-m telescope was commissioned in 1977, and completely upgraded in 1999. Only the f/8 Cassegrain focus is available. In August 2004, the f/8 top end was completely replaced by a new unit permitting the secondary mirror to be actively controlled. This system provides an improved image quality. The pointing error is better than 500RMS. The only available facility instrument, HARPS, is permanently mounted at the Cassegrain focus. The pointing limitations are described inthe 3.6-m pages. Full differential guiding is possible to observe moving targets. 2.2-m Telescope:The 2.2-m telescope is a Ritchey-Chretien design mounted in an equatorial fork mount. It is on loan to ESO from the Max Planck Gesellschaft (MPG) and has been inoperation since 1984.The agreement between ESO and the MPG was extended until March31, 2013. According to this, the MPG is allocated 9 months of observations per year. Accordingly, a preliminary breakdown of the time on the 2.2-m telescope in Period 89 is as follows (from noon of the start date to noon of the end date): from April 1, 2012 to April 29, 2012: MPG time from April 29, 2012 to May 21, 2012: ESO time from May 21, 2012 to June 18, 2012: MPG time from June 18, 2012 to July 2, 2012: ESO time from July 2, 2012 to July 30, 2012: MPG time from July 30, 2012 to August 21, 2012: ESO time from August 21, 2012 to September 17, 2012: MPG time from September 17, 2012 to October 1, 2012: ESO time (These dates may be subject to minor changes.) One night per month during the ESO time slots will be reserved for scheduled technical activities and execution of the calibration plan. In Period 89, ESO will be allocating approximately 67 nights for execution of scientific programmes on the 2.2-m telescope; the corresponding runs will be scheduled exclusively during the ESO time slots. Of these 67 nights, up to 18 will be allocated to Chilean proposals. During ESO time, Visitor Mode runs may be interrupted for target-of-opportunity observations of Gamma-Ray Bursts and X-ray transient afterglows with the GROND instrument of the Max Planck Institute for Extraterrestrial Physics; up to 15% of the time allocation of each run may have to be given away to such observations. A compensation buffer of 10 nights is included in the ESO 67 nights of science time.ESO users whose programmes are affected by GRONDinterruptions are therefore not entitled to any additional compensation. FEROS and WFI are permanently mounted on the telescope. Paranal The VLT Unit Telescopes (UTs):The VLT consists of four Unit Telescopes (UTs). From a user's perspective the four UTs can be regarded as identical. The Paranal Observatory site is located at 70 250longitude West, 24 400latitude South, at an altitude of 2635m. Each UT primary mirror is a single Zerodur blank of diameter 8.20 m, the secondary has a diameter of 1.12 m. The UTs have four foci: two Nasmyth, one Cassegrain, and one Coude. They are Alt-Az mounted and cannot observe at zenith distances less than 4 or larger than 70 . The VLT Interferometer only operates at zenith distances less than 60o. The ATs (VLTI only):The VLT Interferometer is complemented by an array of relocatable 1.8-m Auxiliary Telescopes (ATs). For Period 89 the ATs are offered with MIDI and AMBER. The baselines offered for this period are specified atthe VLTI baseline page. The ATs are equipped with STRAP units, which provide tip-tilt correction for targets with 1:7 < V < 13:5. The distance of the guide star from the science target must be less than 57.500. For observations using the fringe tracker FINITO, V< 11, distance< 1500. While observations on AMBER and MIDI are not affected by the moon there are some restrictions due to the guiding of the telescopes. If the FLI is > 90%, guiding is not possible for stars fainter than 9th magnitude if the distance to the moon is lower than 20 degrees. If the FLI is > 90%, guiding is impossible for any star if the distance to the moon is lower than 10 degrees. Visiting astronomers are requested to check for potential limitations during the preparation of their observations. VISTA:The Visible and Infrared Survey Telescope for Astronomy (VISTA) is a 4-m class wide field survey telescope for the southern hemisphere. VISTA is located at ESO's Cerro Paranal Observatory in Chile on its own peak about 1.5 km from the four UTs. The telescope has an altitude-azimuth mount, and quasi-Ritchey-Chretien optics with a fast f/1 primary mirror giving an f/3.25 focus to the instrument at Cassegrain. Shape and position of the mirrors are actively controlled by high- and low-order curvature wave front sensors (WFS) located inside the instrument focal plane. The low order WFSs are used simultaneously with the scientific observations. VISTA is equipped with VIRCAM. VST:The VLT Survey Telescope (VST) is a 2.6m wide field survey telescope for the southern hemisphere.It is located on the VLT platform on ESO’s Cerro Paranal Observatory and is equipped with justone focal plane instrument, OmegaCAM.The telescope has an altitude-azimuth mount with a f/5.5 modified Ritchey-Chrétien optical layout. It contains an actively controlled meniscus primary mirror, a hexapod driven secondary mirror andan image analysis system. It also contains two interchangeable correctors: one is a high-throughputtwo-lens corrector which provides high throughput from the u to the z band, the other contains anAtmospheric Dispersion Corrector (ADC) for observations at lower elevations. The throughput ofthe ADC is very low in the u band. The entrance window of the OmegaCAM cryostat is the final optical element. The VST operates from the u to the z band, preserving, within a corrected field of view of 1 by 1degree, the excellent seeing conditions achievable at the Cerro Paranal site. Chajnantor The Llano de Chajnantor site is located on 67 450longitude West, 23 000latitude South, at 5104 m altitude in the Chilean Atacama desert. It is a very dry site - inhospitable to humans - but an excellent site for sub-mm astronomy. Water vapour absorbs and attenuates sub-mm radiation and thus a dry site is required for high-frequency radio astronomy.The Atacama LargeMillimeter/submillimeter Array (ALMA) — a collaboration between Europe, North America andEast Asia – is also currently starting early science at the Llano de Chajnantor. ESO has been offering time on the Atacama Pathfinder Experiment (APEX, a 12 meter radio telescope) at the Chajnantor site since Period 77. APEX is an international collaboration involving the Max-Planck-Institut fur Radioastronomie (MPIfR), Onsala Space Observatory (OSO), and ESO.ESO receives 24.7% of the observing time on APEX. The distribution of the observing time betweenthe APEX partners can be found on the APEX web pages. During Period 89, the ESO time isexpected to be scheduled in early April, June and August.Time-critical observations should only be requested during these months. Information partially extracted from the pdf document:ESO Call for Proposals –P89

ESO Telescopes P89

Table of Contents


La Silla

NTT Telescope: The New Technology Telescope is an Alt-Az, 3.5-m Ritchey-Chretien telescope housed in a rotating building designed for optimized air ow. Its thin meniscus Zerodurmirror is controlled in order to maintain the optical figure so that the total aberrations are smaller than 0.1500 (80% encircled energy) -- the NTT was the first telescope to be equipped with “Active Optics". The instruments SofI and EFOSC2 are permanently mounted at the two Nasmyth foci.

The telescope has a pointing accuracy of 200 RMS; objects can be observed at zenithal distances from 2o to 75o. Currently, moving targets can be observed only with differential tracking (not guiding). Moving objects can be followed for up to 15 min with a tracking error smaller than 0.500.

3.6-m telescope: The 3.6-m telescope was commissioned in 1977, and completely upgraded in 1999. Only the f/8 Cassegrain focus is available. In August 2004, the f/8 top end was completely replaced by a new unit permitting the secondary mirror to be actively controlled. This system provides an improved image quality. The pointing error is better than 500 RMS. The only available facility instrument, HARPS, is permanently mounted at the Cassegrain focus. The pointing limitations are described in the 3.6-m pages. Full differential guiding is possible to observe moving targets.

2.2-m Telescope: The 2.2-m telescope is a Ritchey-Chretien design mounted in an equatorial fork mount. It is on loan to ESO from the Max Planck Gesellschaft (MPG) and has been in operation since 1984. The agreement between ESO and the MPG was extended until March 31, 2013. According to this, the MPG is allocated 9 months of observations per year.

Accordingly, a preliminary breakdown of the time on the 2.2-m telescope in Period 89 is as follows (from noon of the start date to noon of the end date):

  • from April 1, 2012 to April 29, 2012: MPG time 
  • from April 29, 2012 to May 21, 2012: ESO time 
  • from May 21, 2012 to June 18, 2012: MPG time 
  • from June 18, 2012 to July 2, 2012: ESO time 
  • from July 2, 2012 to July 30, 2012: MPG time 
  • from July 30, 2012 to August 21, 2012: ESO time 
  • from August 21, 2012 to September 17, 2012: MPG time 
  • from September 17, 2012 to October 1, 2012: ESO time 

(These dates may be subject to minor changes.)

One night per month during the ESO time slots will be reserved for scheduled technical activities and execution of the calibration plan. In Period 89, ESO will be allocating approximately 67 nights for execution of scientific programmes on the 2.2-m telescope; the corresponding runs will be scheduled exclusively during the ESO time slots. Of these 67 nights, up to 18 will be allocated to Chilean proposals.

During ESO time, Visitor Mode runs may be interrupted for target-of-opportunity observations of Gamma-Ray Bursts and X-ray transient afterglows with the GROND instrument of the Max Planck Institute for Extraterrestrial Physics; up to 15% of the time allocation of each run may have to be given away to such observations. A compensation buffer of 10 nights is included in the ESO 67 nights of science time. ESO users whose programmes are affected by GROND interruptions are therefore not entitled to any additional compensation. 

FEROS and WFI are permanently mounted on the telescope.

Paranal

The VLT Unit Telescopes (UTs): The VLT consists of four Unit Telescopes (UTs). From a user's perspective the four UTs can be regarded as identical. The Paranal Observatory site is located at 70 250 longitude West, 24 400latitude South, at an altitude of 2635m.

Each UT primary mirror is a single Zerodur blank of diameter 8.20 m, the secondary has a diameter of 1.12 m. The UTs have four foci: two Nasmyth, one Cassegrain, and one Coude. They are Alt-Az mounted and cannot observe at zenith distances less than 4 or larger than 70 . The VLT Interferometer only operates at zenith distances less than 60o.

The ATs (VLTI only): The VLT Interferometer is complemented by an array of relocatable 1.8-m Auxiliary Telescopes (ATs). For Period 89 the ATs are offered with MIDI and AMBER. The baselines offered for this period are specified at the VLTI baseline page.

The ATs are equipped with STRAP units, which provide tip-tilt correction for targets with 1:7 < V < 13:5. The distance of the guide star from the science target must be less than 57.500. For observations using the fringe tracker FINITO, V< 11, distance< 1500.

While observations on AMBER and MIDI are not affected by the moon there are some restrictions due to the guiding of the telescopes.

If the FLI is > 90%, guiding is not possible for stars fainter than 9th magnitude if the distance to the moon is lower than 20 degrees.

If the FLI is > 90%, guiding is impossible for any star if the distance to the moon is lower than 10 degrees.

Visiting astronomers are requested to check for potential limitations during the preparation of their observations.

VISTA: The Visible and Infrared Survey Telescope for Astronomy (VISTA) is a 4-m class wide field survey telescope for the southern hemisphere. VISTA is located at ESO's Cerro Paranal Observatory in Chile on its own peak about 1.5 km from the four UTs. The telescope has an altitude-azimuth mount, and quasi-Ritchey-Chretien optics with a fast f/1 primary mirror giving an f/3.25 focus to the instrument at Cassegrain. Shape and position of the mirrors are actively controlled by high- and low-order curvature wave front sensors (WFS) located inside the instrument focal plane. The low order WFSs are used simultaneously with the scientific observations.

VISTA is equipped with VIRCAM.

VST: The VLT Survey Telescope (VST) is a 2.6m wide field survey telescope for the southern hemisphere. It is located on the VLT platform on ESO’s Cerro Paranal Observatory and is equipped with just one focal plane instrument, OmegaCAM. The telescope has an altitude-azimuth mount with a f/5.5 modified Ritchey-Chrétien optical layout. 

It contains an actively controlled meniscus primary mirror, a hexapod driven secondary mirror and an image analysis system. It also contains two interchangeable correctors: one is a high-throughput two-lens corrector which provides high throughput from the u to the z band, the other contains an Atmospheric Dispersion Corrector (ADC) for observations at lower elevations. The throughput of the ADC is very low in the u band. The entrance window of the OmegaCAM cryostat is the final 
optical element. 
The VST operates from the u to the z band, preserving, within a corrected field of view of 1 by 1 degree, the excellent seeing conditions achievable at the Cerro Paranal site.
 

Chajnantor

The Llano de Chajnantor site is located on 67 450 longitude West, 23 000 latitude South, at 5104 m altitude in the Chilean Atacama desert. It is a very dry site - inhospitable to humans - but an excellent site for sub-mm astronomy. Water vapour absorbs and attenuates sub-mm radiation and thus a dry site is required for high-frequency radio astronomy. The Atacama Large Millimeter/submillimeter Array (ALMA) — a collaboration between Europe, North America and East Asia – is also currently starting early science at the Llano de Chajnantor. 

ESO has been offering time on the Atacama Pathfinder Experiment (APEX, a 12 meter radio telescope) at the Chajnantor site since Period 77. APEX is an international collaboration involving the Max-Planck-Institut fur Radioastronomie (MPIfR), Onsala Space Observatory (OSO), and ESO. ESO receives 24.7% of the observing time on APEX. The distribution of the observing time between the APEX partners can be found on the APEX web pages. During Period 89, the ESO time is expected to be scheduled in early April, June and August.  Time-critical observations should only be requested during these months.

 

Information partially extracted from the pdf document:  ESO Call  for Proposals – P89